Annls Limnol. 36 (3) 2000 : 169-179

Coffmania, a new tanypod genus from the Darjeeling - Sikkim Himalayas, India (Díptera : )

N. Hazra1 P. K. Chaudhuri1

Keywords : Díptera, Chironomidae, Coffmania, new genus, new species, rheobiontic, embenthic.

A new genus, Coffmania in the tribe of the subfamily with two new species from Darjeeling-Sikkim Himalayas in India is described and illustrated with male and female imagines, pupa and larva. Systematics of the genus and ecology of the species have also been discussed.

Coffmania, un nouveau genre de Tanypodinae (Díptera : Chironomidae) du Darjeeling-Sikkim (Himalaya, Inde)

Mots clés : Diptera, Chironomidae, Coffmania, nouveau genre, nouvelle espèce, rhéobionte, endobenthique.

Les imagos d\ les nymphes de deux espèces nouvelles de la région himalayenne, appartenant à un nouveau genre de Tanypodinae Coffmania de la tribu des Pentaneurini, sont décrits ainsi que l'imago 9 et la larve de l'espèce type C. animispina n. sp. La position systématique du genre et l'écologie des espèces sont aussi discutées.

1. Introduction ving 3-4 ommatidia. The pupa is recognizable by api- cally bifurcate, upwardly directed horn sac and more The chironomids, especially the Tanypodinae, of the or less circular or oval large plastron plate; corona; Indian subregion are less well investigated in compari• thoracic comb; scar on tergite I; dense shagreen most• son to other zoogeographical regions. The finding of ly simple and posteromedially simple, bifid, multi- new taxon is therefore expected. During our survey of branched spinules; 4 and 5 LS setae on segments VU chironomid midges in the Darjeeling-Sikkim Hima• and VTJJ respectively; moderately or strongly hooked layas, a few larvae were collected from the algal mass anal lobe. The larval characteristics include cephalic and also from the sediment of the springs of several index 0.64-0.70; AR 3.4-3.9, blade shorter than flagel- places. On rearing, the adults alongwith the immatures lum; apical half of mandible strongly narrowed and appear as new species under a new genus in the tribe curved, basal tooth very short, no accessory tooth; Pentaneurini. The male imagines are separable from length of segments of b-seta 3,6 and 3; row of teeth of other tanypods by the broad, setose, ovoid or triangu• ligula concave, inner tooth distinctly outcurved; para- lar median volsella with or without lateral lobe; curved ligula about 0.43 length of ligula; pseudoradula consis• and uniformly tapered gonostylus; C slightly produced ting of 7-8 parallel rows forming a band, weakly nar• rowed apically; subbasal seta of posterior parapod and ending proximal to M1+2; scutal tubercle well de• veloped; AR 1.1-1.4 ; narrowest point of the ventral simple and 2 strong supraanal setae. border of the dorsomedial eye extension concave ha- 2. Material and methods The larvae were collected from the algal masses and bottom sediments of the springs in the outskirts of 1. Department of Zoology, University of Burdwan, Burdwan, 713 Gangtok, Jorethang (Sikkim), Mirik (West Bengal) 104, India. and were subjected to rearing in the laboratory. The

Article available at http://www.limnology-journal.org or http://dx.doi.org/10.1051/limn/2000015 170 N. HAZRA, RK. CHAUDHURI (2)

imagines and the immatures are processed and moun• mid leg with or without tarsal brush; claws slender, ted on microslides following the methods by Das Gup• distally pointed; pulvilli absent. ta & Wirth (1968). The general morphological termi• Abdomen. Yellow to light brown; posterior border of nology follows Saether (1980). The measurements of tergite IX concave, transverse row of setae present or different parts of immatures and adults are taken with absent. the help of microscope and micrometer and are expres• sed in micrometer (|Lim). However, total length of pu• Hypopygium. Anal point broad and conical; gono- pae and larvae, and total length and wing of adults are coxite robust more or less cylindrical, 1.4-1.5 x as long expressed in millimeter (mm). The measurements are as broad, inner border straight, outer border convex, given as ranges followed by «n» ensuring the number slightly tapered distally, dorsomedian surface with of specimens observed. 15-18 large, erect apical setae; median vulsella broad, setose, ovoid or triangular in shape with or without fin• Types are at the Entomological collections of the University of Burdwan and will be deposited in Natio• ger-like lateral lobe; gonostylus long, slender, curved nal Zoological Collections (NZC) Calcutta, in British with swollen base bearing large megaseta; phallapode- Natural History Museum (BMNH) London and in U.S. me distinct, simple, sternapodeme pointed anteriorly. National Museum (USNM) Washington D. C, in due - Female imago course. Similar to male except for following differences : AR 0.22-0.26; antenna 12 segmented. LRj 0.81-0.87, 3. Coffmania gen. n. LR2 0.60-0.66 and LR3 0.73-0.74. Genitalia with well Type species. Coffmania animispina sp. n. by pre• developed gonocoxite VIII bearing few strong setae; sent designation. segment X normal; gonapophysis VIII with large ven• trolateral lobe; apódeme lobe with curved and distinct Etymology. The genus is named in honour of Pr. W. apódeme; cercus small; seminal capsule round with P. Coffman of Pittsburgh University in recognition of well developed sclerotized neck; notum long with his valuable contributions to the study of Chironomi- dae. strongly diverged rami. - Pupa 3.1. Diagnosis Small to medium sized pupae, up to 4.70 long. Exu• - Male imago viae pale brown. Small species; wing length 1.5-1.8. Céphalothorax. Thoracic horn flatfish, swollen api- Head. Eye with dorsomedial extension with 3-4 om- cally and 1.55-2.1 x as long as broad, external mem• matidia at minimum width, ventral border of the eye brane spinose, horn sac tubular, apically bifurcated extension especially at the narrowest point distinctly overlapping to the plastron plate, plastron plate oval or concave. Antenna. AR 1.1-1.4; pedicel yellow, termi• circular in shape, corona present, occupying 0.40-0.70 nal flagellomere not offset basally 3.2-4.5 x as long as horn length; thoracic comb present but weak; small ba• broad and tapering in the distal 1/3. Head yellowish in sal lobe present. Thoracic membrane spinose. Scutal colour. TV, OV and Po uniserial. tubercle and postnotal tubercle absent. Thoracic setae

Thorax. Antepronotum well developed, lobes sepa• Dcj, Dc2, and Sa simple, distally pointed. rated above with 5-6 lateral antepronotals; acrostichals Abdomen. Scar on tergite I elongated, lightly pig• biserial between the vittae, diverging in front of the mented. Tergites and sternites with a dense covering of scutal tubercle and ending in the prescutellar field, simple, bifid and multibranched shagreen spinules. dorsocentrals irregularly biserial anteriorly, uniserial Apophyses present. D and V setae filamentous, termi• posteriorly, prealars numerous, mostly robust; scutal nally round, L seta filamentous on segment I and tubercle very distinct. simple on segments II-VI, longer than D seta. LS setae Wing. Membrane with setae with or without faint always present on segments VII-VIII. Anal lobe band; brachiolum with 2 setae; C slightly produced 2.18-2.30 x as long as broad, dorsal surface with beyond R^, ending well before M1+2, R2+3 distinct, simple spinules, inner border slightly convex with or FCu before MCu; anal lobe weakly developed. without spinules and outer border concave distally wi• Legs. Pale yellow in colour; tibial spurs elongate wi• th fine spinules, apex of anal lobe hooked; anal macro- th main tooth 0.5-0.65 spur length and 5-8 lateral tee• setae without adhesive sheaths; male genital sac rea• th; tibial comb of 5-7 setae present on hind leg; Ta3 on ching 0.65-0.71 of anal lobe length. (3) COFFMANIA, A NEW TANYPOD GENUS FROM THE DARJEELING - SIKKIM 171

- Larva simple, larger claws with small, fine points on inner Medium sized larvae, up to 6 long. Head capsule margin. elongate brown in colour, posterior margin blackish 3.2. Systematics brown, head capsule longish-oval, cephalic index 0.64-0.70. In the key of adult tanypod males of Holarctic chiro- nomids (Murray & Fittkau 1989) Coffmania will key Antenna. AR 3.45-3.87; antenna almost 1/2 as long to couplet 21, consisting of the genera Hayesomyia as head, 2.25-2.40 x as long as mandible; basal seg• Murray and Fittkau, Telopelopia Roback, Helopelopia ment about 10 x as long as basal width, with ring organ Roback and Conchapelopia Fittkau. Similarly in the at the base of apical 1/3, segment II about 8.5-9.5 x as key of tanypod pupae of Holarctic chironomids (Fitt• long as wide, apical segment 3/4 as long as segment kau & Murray 1986), Coffmania will key to couplet III; style clubbed apically, reaching to about middle of 28, consisting of the genera Conchapelopia, Merope- last segment; blade somewhat shorter than fllagellum, lopia Roback, Telopelopia and Helopelopia. The new blade about 4.5 x as long as height of basal ring, basal taxon bears diffused characters with the other genera ring 2 x as high as wide, accessory blade shorter than of the Thienemannimyia group and seems to be allied blade. to genus Conchapelopia nepalic ola-gxoxxp (Murray Mandible. Apical 1/2 of mandible strongly narrowed 1976) of the Conchapelopia and Telopelopia Roback and curved, 2 x as long as basal width, basal half because of the presence of scutal tubercle. The median 1/2 strongly broadened, apical tooth 2.50 x as long as vulsella comes nearer to those of Rheopelopia Fittkau basal width, about 1/4 length of mandible, distal and Thienemannimyia Fittkau. The new species Coff• 1/2 blackish brown; basal tooth insignificant, seta sub- mania adiecta proposed under the new genus also pos• dentalis arising from dorsal side; accessory tooth not sesses elongate, finger-like lateral lobe as noted in so• visible, ventrolateral setae adjacent to the outer margin me Rheopelopia (maculipennis-group) and Hayeso• of basal 1/2 of mandible, sensillum minusculum situa• myia. The setae on the posterior border of tergite IX ei• ted proximal to seta III, ventrolateral seta I small, peg• ther form a continuous row as in Thienemannimyia, like, seta II simple and seta III divided, setae I and II Rheopelopia, nepalicola-group and Hayesomyia or ab• close together, gap between setae II and III 5-7 long. sent as in Conchapelopia, Helopelopia and Telopelo•

Maxilla. Basal segment of maxillary palp almost pia. Ta3 of midleg possesses either tarsal brush like 4 x as long as wide with ring organ at the base of api• that of Conchapelopia, Helopelopia or without tarsal cal 1/3, b-seta 3 segmented, middle segment 2 x as brush as in Thienemannimyia, Telopelopia, Meropelo- long as basal or apical segment. pia and Hayesomyia. Apically bifurcate horn sac of pupa bears some resemblances with that of Conchape• Mentum and M appendage. Dorsomentum without lopia pallidula (Meigen 1818). Similarly, LS setae on teeth, a sclerotized complex on each side of base of M abdominal segments VII and VIII are like those of appendage and from which labial vesicles on each side Conchapelopia and Hayesomyia. In the same way, ending in 2 overlapping, blunt points; M appendage apex of anal lobe is moderately to strongly hooked as triangular and snout-like; labial vesicle elongated; in Rheopelopia. The larva seems to be a typical pseudoradula relatively narrow band, narrowed to• Conchapelopia larva in respect to antenna, b-seta of wards apex, granulation comprising of 7-8 closely ad• maxillary palp, mandible, ligula and subbasal seta of jacent parallel rows. posterior parapods. Male pupa of Pentaneurini sp.l Ligula and paraligula. With concave row of 5 teeth, described by Roback & Coffman (1989) from Sou• almost 2 x as long as apical width, apical 1/3 brownish thern India bears close affinities with the Coffmania black, middle tooth 2 x as long as wide, apex of inner animispina proposed in the new genus in median vul• tooth distinctly outcurved. Paraligula bifid about sella of male hypopygium, thoracic horn, shagreen pat• 0.43 length of ligula, outer point 2 x as long as inner tern, anal lobe and G/Fbut differs in location of LS se• point. tae on segments VU and VIII, ALR. AR and b-seta of Pectén hypopharyngis. With 17-18 teeth more or larva of Pentaneurini sp. 1 differ with the new genus. less equal in length, outermost tooth smaller. It is worthy to mention *hat 4he pupa being described Body. Without fringe of swim-setae. Anal tubules here almost conforms with that of Pentaneurini sp. 1 slender, spindle-shaped, about 5 x as long as wide. described by Roback & Coffman (1989) from Sou• Posterior parapod bearing a subbasal simple seta. Pro- thern India. Therefore, in our opinion, the pupa of Pen• cercus about 3 x as long as wide with 7 anal and taneurini sp. 1 should be treated under the new genus 2 strong supraanal setae. Claws of posterior parapod Coffmania. 172 N. HAZRA, RK. CHAUDHURI (4)

3.3. Key to the male imagines of the genus Coffma• Abdomen. Tergite LX without transverse row of se• nia gen. n. from Darjeeling-Sikkim Himalayas tae. 1. Median vulsella with elongate finger-like lateral Hypopygium (Fig. lB).Gonocoxite 148 long, 1.5 x lobe. Ta3 of mid leg with tarsal brush as long as broad; median volsella (Fig. broad, se• adiecta sp. n. tose, swollen apically with elongate finger-like lateral — Median vulsella without lateral lobe. Tarsal bru• lobe; gonostylus slender, curved 140 long with 11 long megaseta; phallapodeme 107 long, sternapodeme 92 sh on Ta of mid leg absent animispina sp. n. 3 long; HR 1.05; HV 2.32. 3.4. Key to the pupae of the genus Coffmania gen. n. - Female : unknown. from Darjeeling-Sikkim Himalayas - Pupa (n=l) 1. Plastron plate occupying 0.75 length of the tho• Total length of exuviae 4.07. Pale brown in colour. racic horn. Inner border of anal lobe lacking spi• nules adiecta sp. n. Céphalothorax. Thoracic horn (Fig. 2A) 322 long, Thr 1.65, plastron plate occupying 0.75 horn length; — Plastron plate occupying 0.40-0.65 length of the thoracic comb as in the Fig. 2Aj. horn. Inner border of anal lobe with 8-11 spi• nules animispina sp. n. Abdomen. Scar on tergite I (Fig. 2B) 157 long, occu• pying 0.80 length of the segment I. Segments I-VIII

3.5. The Thienemannimyia group with mostly simple (Fig. 2CY) and posteromedial^ simple, bifid and multibranched spinules (Fig. 2C ). Coffmania adiecta sp. n. (Figs. 1 A-B 2 A-F) 2 l5 Arrangement of setae on segment IV as in the Fig. 2D. Type material. Holotype O" (Type no. B.U.Ent. 230) Segment VII (Fig. 2E) with 202 long 4 LS setae placed with pupa [reared], Sikkim, Jorethang, 08-IX-1996, 0.57,0.67,0.76 and 0.84 from base; segment VIII (Fig. coll. N. Hazra. Paratype 1 ($ with pupa, data as holoty• 2F) with 480 long 5 LS setae placed 0.49, 0.58, 0.76, pe. 0.88 and 0.92 from base. Anal lobe (Fig. 2F) 322 long, — Male imago (n=l) 333 wide without inner spinules and with several outer Total length 3.25; wing length 1.74; total length / spinules plus 2 anal macrosetae placed 0.41 and 0.55 wing length 1.87; wing length / profemur length 1.74. from base; G/F 0.70 in male; ALR 1.94. Head. Eye with 139 long dorsomedial extension. - Larva : unknown. AR 1.32; length of flagellomeres (I-XIV) : 41,22, 35, Remarks 35, 35, 35, 35, 35, 35, 35, 35, 35, 455, 92. Temporal Owing to presence of a lateral lobe on the median setae 14 (4 IV, 7 OV, 3 Po). Clypeus with 29 setae. volsella of the male hypopygium, the species has been Length of palpomeres : 55, 78, 165, 195, 225. CA named as Coffmania adiecta. The diagnosis characters 0.57; CP 0.75. of the species are : Thorax. Acrostichals 33 biserial between the vittae Male imago, i) Median volsella broad, setose swol• and 15 between scutal tubercle and prescutellar field; len epically with elongate finger-like lateral lobe, ii) dorsocentrals 30, prealars 18, supraalar 1; scutellum AR 1.32, iii) squamal setae 22, iv) HR 1.05 and v) Ta with 16 large and 17 small setae. 3 of mid leg with tarsal brush. Wing (Fig. 1A). VR 0.87; CR 0.93; costal extension Pupa, i) Plastron plate occupying 0.75 length of the 48; squama with 22 setae. horn, ii) Thr 1.65, iii) LSt seta on segment VU at 0.57 Leg. Spur of fore tibia 37 long bearing 7 lateral tee• segment length, iv) apex of anal lobe moderately hoo• th, spurs of mid tibia 46 and 48 long bearing 7 and 8 la• ked, v) ALR 1.94 and vi) G/F 0.70. teral teeth, spurs of hind tibia 41 and 66 long bearing 6 lateral teeth each. Ta3 of mid leg with tarsal brush. Coffmania animispina sp. n. (Figs. 3 A-E, 4, 5 A-F, Lengths and proportions of leg segments: 6A-G) Type material. Holotype cf with pupa [reared] (Type

Fe Ti taj ta2 ta3 ta4 ta5 LR BV SV BR no. B.U. Ent. 231), Sikkim, Tadong, 08-IV-1996, coll. N. Hazra. Paratypes 3 C?cF and 3 99 with larvae and p : 810 960 840 450 315 225 120 0.87 2.35 2.68 4.33 t pupae [reared], data same as above; 1 (S and 1 9 with pupae [reared], Sikkim, Jorethang, 27-V-1996, coll. N. p2: 885 970 570 277 195 150 90 0.58 3.40 4.26 4.61 Hazra; 1 9 with larva and pupa [reared], West Bengal, p : 780 1065 840 450 330 225 120 0.78 2.38 2.73 5.71 3 Mirik, 03-LX-1996, coll. N. Hazra. COFFMANIA, A NEW TANYPOD GENUS FROM THE DARJEELING - SIKKIM

Fig. 1. Male imago of Coffmania adiecta n. sp. : A. wing; B. hypopygium ; Bp enlarged median vulsella. Fig. 1. Imago mâle de Coffmania adiecta n. sp. : A. aile; B. hypopyge ; Bp volsella médiane agrandie. 174 N. HAZRA, P.K. CHAUDHURI (6)

Fig. 2. Pupa of Coffmania adiecta n. sp. : A. thoracic horn ; A,, thoracic comb ; B. tergite I; C,. shagreen on anterior part of tergite IV; C2. sha• green on posteromedial part of tergite IV; D. tergite IV; E. segments VI-VIII and anal lobe ; F. anal lobe and male genital sac. Fig. 2. Nymphe de Coffmania adiecta n. sp.: A. corne thoracique ; A, peigne thoracique ; B. tergite I; C,. chagrin sur la partie antérieure du ter•

gite rV; C2. chagrin sur la partie postéro-médiane du tergite IV; D. tergite IV; E. segments VI-VIH et lobe anal; F. lobe anal et sac génital mâle. (7) COFFMANIA, A NEW TANYPOD GENUS FROM THE DARJEELING - SIKKIM 175

Fig. 3. Male imago of Coffmania animispina n. sp. : A. thorax ; A,. scutal tubercle ; B. wing; CrC3. tibial spurs on fore leg, mid leg and hind leg ; D. claw; E. hypopygium.

Fig. 3.Imago mâle de Coffmania animispina n. sp. : A. thorax ; A,, tubercule scutal ; B. aile; Ci-C3. éperons des tibias des pattes antérieures, moyennes et postérieures; D. griffe; E. hypopyge. 176 N. HAZRA, RK. CHAUDHURI (8)

Fe Ti ta, ta 2 to3 ta4 ta5

Pl 690-870 810-1005 705-915 330-450 240-315 165-225 105-120

P2 765-945 750-930 465-585 210-270 165-210 127-165 82-105

p3: 645-870 930-1162 750-930 375-510 285-375 165-240 105-120 ©

1 _ LR BV SV BR

P! : 0.87-0.91 2.22-2.51 2.90-2.94 4.00-4.66

P2 0.62-0.63 3.28-3.38 3.90-4.04 4.97-5.16 0.80 2.15-2.37 2.76-2.83 5.83-6.00

Abdomen. 16-18 setae on posterior border of tergite LX forming a single row or setae absent. Hypopygium (Fig. 3E). Gonocoxite 129-155 long, 1.4 x as long as broad; median volsella setose, ovoid or Fig. 4. Female genitalia of Coffmania animispina n. sp. triangular in shape; gonostylus 129-144 long, slender, Fig. 4. Genitalia femelle de Coffmania animispina n. sp uniformly tapered with 13-16 long megaseta; sterna- podeme 75-96 long, phallapodeme 70-92 long; HR 1.00-1.07; HV 2.43-2.74. - Male imago (n=4, except when otherwise stated) - Female imago (n=4, except when otherwise sta• Total length 3.14-3.77; wing length 1.52-1.85; total ted) length / wing length 1.91-2.03; wing length / length of profemur 1.78-2.15. Similar to male with usual sex differences : Head. Eyes with 158-180 long dorsomedial exten• Genitalia (Fig. 4). Gonapophysis VIII with inner sion. AR 1.14-1.36; length of flagellomeres (I-XIV) : margin of ventrolateral lobe strongly projecting to• 29-33, 18-26, 30-33, 33-37, 33-37, 33-37, 33-37, 33- wards inner margin of opposite lobe; vaginal opening 37, 33-37, 33-37, 33-37, 33-37, 359-433, 78-81. Tem• oval, hinge weakly sclerotized with apex directed dis- poral setae 15-18 (4-5IV, 8-9 OV, 3-4 Po). Clypeus wi• tolaterally; gonocoxite VIII with 6-8 setae; cercus 40- th 16-24 setae. Length of palpomeres : 37-48, 74-82, 48 long; seminal capsule 51-62 in diameter; notum 92- 120-150, 165-187, 225-285. CA 0.51-0.57; CP 0.72- 111 long. 0.78. - Pupa (n=5, except when otherwise stated) Thorax (Fig. 3A). Acrostichals 17-36 biserial bet• Length of exuviae 4.25-4.66 long, pale brown in co• ween the vittae, 10-26 diverging in front of the scutal lour. tubercle (Fig. 3A1) and extending to the prescutellar Céphalothorax. Thoracic horn (Fig. 5A) 277-345 field; dorsocentrals 23-32, prealars 12-20, supraalars long, Thr 1.72-2.1, plastron plate occupying 0.40-0.65 2; scutellum with 10-21 large and 13-18 small setae. horn length; thoracic comb small, as in the Figs. 5A!.

Wing (Fig. 3B). VR 0.82-0.88; CR 0.91-0.93; sen- Dc,, Dc2 and Sa 33-48 long. silla camponiformia 24-26; costal extension 55-59 Abdomen. Scar on tergite I (Fig. 5B) 150-195 long, long; squama with 20-23 setae. cylindrical, occupying 0.83-0.92 length of the seg• Leg. Spur of fore tibia (Fig. 3Cj) 33-41 long bearing ment. Segment I with simple as well as bifid spinules,

6-8 lateral teeth, spurs of mid tibia (Fig. 3C2) unequal segments II-VIII with mostly simple spinules (Fig. 39-42 and 44-50 long bearing 7 and 8 lateral teeth, 5Ci) and posteromedial^ simple, bifid and multibran- spurs of hind tibia (Fig. 3C3) 33-40 and 59-70 long ched spinules (Fig. 5C2). Setal pattern on tergite TV as bearing 5 and 6 lateral teeth; width at the apex of fore in the Fig. 5D; 210-300 long 4 LS setae (Fig. 5E) pla• tibia 39-45, mid tibia 41-52 and hind tibia 41-48; claws ced on segment VII at 0.54-0.68, 0.65-0.76, 0.77-0.84, as in the Fig. 3D. and 0.86-0.92 of segment length; 450-525 long 5 LS Lengths and proportions of leg segments: setae on segment VIII at 0.50-0.58, 0.62-0.69, 0.71- (9) COFFMANIA, A NEW TAN Y POD GENUS FROM THE DARJEELING - SIKKIM 177

Fig. 5. Pupa of Coffmania animispina n. sp. : A. thoracic horn ; A,, thoracic comb ; B. tergite I ; Cp shagreen on anterior part of tergite IV ; C2. shagreen on posteromedial part of tergite IV; D. tergite IV; E. segments VI-VIII and anal lobe ; F. anal lobe and male genital sac ; Fl. enlar• ged apex of anal lobe. Fig. 5. Nymphe de Coffmania animispina n. sp. : A. corne thoracique ; A,, peigne thoracique ; B. tergite I ; C,. chagrin sur la partie antérieure du

tergite IV ; C2. chagrin sur la partie postéro-médiane du tergite IV; D. tergite IV; E. segments VI-VHI et lobe anal; F. lobe anal et sac génital mâle; Fl.apex agrandi du lobe anal. 178 N. HAZRA, RK. CHAUDHURI (10)

Fig. 6. Larva of Coffmania animispina n. sp. : A. antenna ; A,, apex of antenna ; B. mandible; C. maxillary palp ; D. mentum and m appendage; E. ligula and paraligula; F. pectén hypopharyngis; G. claws of posterior parapod. Fig. 6. Larve de Coffmania animispina n. sp. : A. antenne ; A,, apex de l'antenne ; B. mandibule; C. palpe maxillaire; D. mentum; E. ligula et pa• raligula; F. peigne de l'hypopharynx; G. crochets des parapodes postérieurs. (11) COFFMANIA, A NEW TANYPOD GENUS FROM THE DARJEELING - SIKKIM 179

0.80, 0.83-0.90 and 0.94-0.97 of segment length. Anal v) length of segments of b-seta 3, 6 and 3, vi) ligula lobe (Fig. 5F) 330-390 long, 300-338 wide with 8-11 bearing concave row of teeth, vii) paraligula 0.43 leng• inner spinules, several outer spinules and anal macro- th of ligula, viii) pseudoradula consisting of 7-8 paral• setae placed at 0.39-0.43 and 0.52-0.56 lobe length; lel rows and ix) 2 strong supraanal setae. G/F 0.65-0.71 in male; ALR 2.18-2.31. - Larva (n=3, except when otherwise stated) 4. Ecology Total length 5.40-6.00. Head capsule brown in co• lour, cephalic index 0.64-0.70. Immatures are rheobiontic and embenthic living in Antenna (Figs. ÓA-A^. AR 3.45-3.87; length of an- cool, small sized, shallow springs. They prefer algal tennal segments (I-IV) : 211-222, 44-50, 6-7, 5-5.5; mats of more or less hygropetric biotopes with slow to style 7-10 long; blade 53-56 long, accessory blade moderate flow. The tanypod larvae remain usually in 49-53 long. close association with orthoclad larvae of genus Para- cricotopus Thienemann and Harnisch which are consi• Mandible (Fig. 6B). 111-122 long; apical tooth dered as their predominant food in addition to algae, 26-30 long; seta subdentalis 19-22 long. detritus and other chironomid larvae. Maxilla (Fig. 6C). Basal segment of palp 40-44 long; length of segments of b-seta 3, 6 and 3. Acknowledgements Mentum and M appendages (Fig. 6D). Labial vesicle Thanks are due to the Department of Science & Technology, 18-22 long; pseudoradula 77-85 long, basal width 11-15. Govt, of India, New Delhi for providing fund for the project and to the Head of the Department of Zoology, University of Burdwan and Ligula (Fig. 6E). 77-86 long, middle tooth 9-11 long Postgraduate Department of Zoology, Darjeeling Govt. College for and inner tooth 11-14 long. laboratory facilities. We express our indebtness to Dr. Xinhua Wang, Paraligula (Fig. 6E). 35-37 long; inner point 7-9 Department of Biology, Nankai University for kindly reading the manuscript and for making valuable comments. long and outer point 15-18 long.

Pectén hypopharyngis (Fig. 6F). 17-18 teeth. References Body. Anal tubule 111-140 long, 22-29 wide; subba- Das Gupta S.K. & Wirth W.W. 1968. — Revision of Oriental species sal seta 170-185 long; procercus 88-93 long, 28-32 wi• of Stilobezzia Kieffer (Díptera : Ceratopogonidae). Bull. U. S. de with 375-450 long anal setae; supraanal seta Nat. Mus., 283 : 1-264. 345-375 long; claws of posterior parapods as in the Fittkau E.J. & Murray D.A. 1986. — The pupae of Tanypodinae (Diptera : Chironomidae) of the Holarctic region - Keys and dia• Fig. 6G. gnoses. In Wiederholm, T. (ed.) Chironomidae of the Holarctic Remarks region, Keys and diagnoses, Part 2 - Pupae. Ent. Scand,. Suppl. 28:31-113. In view of the presence of spines in the inner border Meigen J.W. 1818. — Systematische Beschreibung der bekannten of the anal lobe of pupa, the species has been named as europàischen zweiflugeligen Insekten. Erster Teil Aachen. Coffmania animispina. The diagnosis characters of the Murray D.A. 1976. — Four new species of Conchapelopia Fittkau species are : from Nepal with a discussion of the phylogeny of the nepalicola- group (Diptera : Chironomidae). Ent. Scand., Suppl. 7 : 293-301. Male imago, i) Median volsella setose, ovoid or tri• Murray D.A. & Fittkau E.J. 1989. — The adult males of Tanypodi• angular in shape, ii) tergite IX with 16-18 setae in nae (Diptera : Chironomidae) of the Holarctic region - Keys and transverse row or without setae, iii) squamal setae diagnoses. In Wiederholm, T. (ed.) Chironomidae of the Holarctic region, Keys and diagnoses, Part 3 - Adult males. Ent. Scand., 20-22, iv) AR 1.14-1.36 and v) HR 1.00-1.07. Suppl. 34 : 37-123. Pupa, i) Plastron plate occupying 0.40-0.65 length Roback S.S. & Coffrhan W.P. 1989. — Tanypodinae pupae from of the horn, ii) Thr 1.72-2.10, iii) LSi seta on segment Southern India (Diptera : Chironomidae). Proc. Acad. Nat. Sc. VII at 0.54-0.68 segment length, iv) apex of anal lobe Philad., 141 : 85-113. Saether O.A. 1974. — Morphology and terminology of female geni• moderately or strongly hooked, y) inner border of anal talia in Chironomidae (Diptera). Ent. Tidskr., Suppl. 95 : 216-224. lobe with 8-11 spinules, vi) ALR 2.18-2.31 and vii) Saether O.A. 1977. — Female genitalia in Chironomidae and other G/F 0.65-0.71 in male. : morphology, phylogenies, keys. Bull. Fish. Res. Bd. Can., 197 : 1-209. Larva, i) Cephalic index 0.64, ii) AR 3.4-3.9, iii) Saether O.A. 1980. — Glossary of Chironomid morphology termi• blade shorter than flagellum, iv) basal tooth very short, nology (Diptera : Chironomidae). Ent. Scand., Suppl. 14 : 1-51.